How to recognize a ball in an image and then model it in 3D(HawkEye System)

Question

We are trying to develop HawkEye System used in cricket for our college project. The process used in HawkEye System is as follows:

1. images of the the ba

Answer 1

Give your ball a distictive colour that you are unlikely to find elsewhere in the image, then look for pixels in that colour in each image. This is the easiest option. Given the speed at which a ball could move in cricket and you are using only 30 fps most other options are much more difficult. Just finding a white ball is quite difficult (as you probably found) so your best bet would be to use the information about the movement of the ball in previous frames to help find it in new frames. However, low frame rate and high ball speed means your ball will move quite a bit between frames. At 142 km/h for a high speed bowl you are looking at more than one meter of movement between frames, which will result in quite a large gap between the images of the ball between subsequent frames, and this makes using the temporal information more difficult.

As an alternative to a weird colour you could also paint your ball with a layer that is highly reflective in the IR domain and use IR lights (which humans can't see) and IR sensitive camera's (you could remove the IR filter from the camera's you have for this).